WSL is always good for some unexpected surprise. Which, on the first glance may look like a problem in VSCode. But it wasn’t.
The problem: VSCode couldn’t connect to WSL and gave the message “Could not fetch remote environment”.
A web search for this error message lead to an entry on
Stackoverflow which indicated some version and update
issues in VSCode. Since neither of the solutions worked and I additionally
apt update and WSL internet access in general stopped working, I
concluded that I had broken WSL altogether.
The only bigger system change I’d done on that day was compressing
C:\Users\<yourname>\AppData. I had some faint memory that compressing certain
folders could confuse WSL. Luckily, my first guess seemed to be correct:
C:\Users\<yourname>\AppData\Local\Temp restored WSL internet
connection as well as VSCode access to the WSL.